1. Field of the Invention
The present invention relates to a developing method using a two-component developer. In addition, the present invention also relates to an image forming method using the developing method.
2. Description of the Related Art
Conventionally, electrophotographic image forming methods using a two-component developing method are known. The image forming methods typically include the following processes:
(1) Forming an electrostatic latent image on an image bearing member such as a photoreceptor;
(2) Developing the electrostatic latent image with a two-component developer including a toner and a carrier to form a toner image on the image bearing member;
(3) Transferring the toner image onto a recording material; and
(4) Fixing the toner image on the recording material, resulting in formation of an output image.
A coated carrier having a configuration such that a cover layer, which includes a material having a low surface energy such as fluorine-containing resins and silicone resins, is located on the surface of a particulate core material is typically used as the carrier of the two-component developer.
There is a proposal for a carrier having a particulate magnetic core material and a cover layer, which is located on the surface of the core material and which includes a crosslinked resin obtained by crosslinking a copolymer, which is obtained by reacting an organopolysiloxane having a vinyl group at the end thereof with a radically polymerizable monomer having at least one functional group selected from the group consisting of hydroxyl, amino, amide and imide groups, using an isocyanate compound.
Recently, in order to produce high quality images, the diameter of toner used for the two-component developer becomes smaller and smaller. In addition, electrophotographic image forming methods have been used for print-on-demand fields, and there is a strong need for a super-high speed electrophotographic image forming apparatus having a higher print speed than conventional high-speed electrophotographic image forming apparatuses.
However, such a super-high speed electrophotographic image forming apparatus easily causes a problem in that the charging property and volume resistivity of the carrier used for the developer thereof seriously change, resulting in deterioration of image qualities.
For these reasons, the inventors recognized that there is a need for a carrier which does not cause the above-mentioned problem even when being used for super-high speed image forming apparatuses.